1. Field of the Invention
This invention relates to the field of disposable holders and mailers of the type used for conveying medical specimen slides from a sample collection site to a clinical laboratory site, and in particular concerns such holders featuring an integral closure for keeping the slide holder closed.
2. State of the Prior Art
Medical specimens such as tissue and fluid samples are frequently collected slides on small strips of glass by an examining physician or medical technician and sent to a clinical laboratory for analysis. During transport it is necessary to protect the slide and the specimen material against loss and contamination. For this purpose various slide holders and mailers have been devised and are in widespread use. The mailers are typically designed to be disposable and are made of low cost materials such as cardboard or plastic. Cardboard slide holders are in particularly widespread usage because of their low cost and relative convenience and effectiveness. These are typically made of corrugated cardboard and are available in different sizes and configurations designed for holding different numbers of specimen slides, from a single slide to many slides.
Cardboard slide holders are manufactured by die cutting flat sheets of cardboard to make one-piece cardboard blanks which are then folded and glued to make the finished slide holder. The finished holder has a cover portion and a tray portion hinged to each other along a fold line of the blank. The specimen slide or slides are held between the tray and the cover when the holder is folded to a closed condition. In U.S. Pat. No. 5,611,433 which is incorporated by this reference as if fully set forth herein, this applicant disclosed an improved cardboard slide holder featuring a recess in the cover portion of the holder. The recess overlies the specimen bearing area of the slide preventing contact between the holder and the specimen. Conventional cardboard holders which lack the aforementioned feature also remain in common use. A shortcoming common to all these cardboard slide holders is the absence of any convenient means for keeping the holder closed during handling and transport. Presently this is accomplished by applying a piece of adhesive tape over the edges of the closed holder to keep it from opening. This requires the user to provide the piece of tape which is a significant inconvenience. Also, adhesive tape once removed does not adhere very well so that once the slide holder has been closed it cannot be reclosed without a fresh piece of tape. The tape is not easily removed and the most expedient method of opening the slide holder is by cutting the tape. In an effort to overcome some of these difficulties, some cardboard slide holders have been provided with patches of contact adhesive. These eliminate the need for providing a separate piece of tape but add significantly to the cost of the holder and normally require a covering of release sheet material which is removed to expose the adhesive just prior to closing the holder, making the holder more difficult to handle.
A continuing need exists for slide holders having a more convenient, reusable closure which does not add materially to the cost of the disposable slide holder.